loadrunner input parameter vs output parameter

[kernelkoder]

i check vugen pdf user guide, it said

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Input parameters are parameters whose value you define in the design stage
before running the script. Output parameters you define during design
stage, but they acquire values during test execution. Output parameters are
often used with Web Service calls.
Use care when selecting a parameter for your script during design stage,
make sure that it is not an empty Output parameter.

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can you give me example, what is input parameter and output parameter?

[bighead337]

I never really distinguished the two types but this is how I see it explained.

Input: Parameter added before script execution and is used for execution of the script. Examples would be like username and passwords you use to loadtest a login step using multiple different login accounts.

Output: Parameters saved from the execution of a script. Vugen PDF points to it being used mostly in Web Services script where there's an actual field you can set to saved the Web Service Call response as a parameter.

Although it points to Web Services, a regular web script can contain code to capture a parameter and reuse it too but that's consider correlation. Maybe the only difference is that the Web Service script contains a LR Vugen UI to specifically save the content as a parameter just like it does for adding username/passwords into the Parameter List.